The known drive axles, in particular the adjustable drive axles, comprise two axle shafts each having two portions slidingly inserted one into the other. The hubs for the support of the wheels are fixed to the sliding positions of the axle shafts. In this way, the drive axle can be configured to assume a minimum track configuration and a maximum track configuration.
The hubs can be rigidly fixed to the sliding portions. In such case, a rigid drive axle or, in other words, nonsteering, is created.
Alternatively, the hubs can be rotatably bound to the sliding portions, thus defining a steering drive axle.
The drive axles of known type, disadvantageously, introduce problems in the stability of the coupling of the fixed and sliding portions of the axle shafts. This problem is further exacerbated by the fact that these axles are intended for agricultural or industrial machines that operate, obviously, on naturally uneven terrains like fields or work site roads.
Moreover, an additional disadvantage that can be identified in known drive axles is that the selectable configurations are only those of minimum and maximum track.